1. Field of the Invention
The present invention relates to an electrical connector having a structure for recognizing an incomplete insertion state of a terminal in the connector housing. A resilient lock arm is disposed in the connector housing for locking the terminal, and a spacer is inserted in the connector housing for additionally locking the terminal inserted in the connector housing. The spacer abuts against the resilient arm when the terminal is incompletely inserted in the connector housing to recognize the incomplete insertion of the terminal.
2. Related Art
Referring to FIGS. 15 and 16, there is illustrated a conventional electrical connector 90 having a terminal double locking structure. The structure has a function for recognizing an incomplete insertion state of the terminal in the connector housing.
As illustrated in FIG. 15, the terminal double locking connector 90 has a synthetic resin connector housing 91, a plurality of terminals 92 each connected to an electrical cable and upwardly inserted into the connector housing 91, and a synthetic resin spacer 97 laterally inserted into the connector housing 91 through openings of the connector housing 91. The spacer 97 has a pair of first extending bars 94 each engaging with a rear surface of a step 93 formed in a rear part of each terminal 92. The spacer 97 also has a second extending bar 95 that advances into a housing space in which a resilient lock arm 96 (FIG. 16) for each terminal deflects.
The second bar 95 of the spacer 97 has a fore end abutting against a side surface of the lock arm 96 in an incomplete insertion state of the terminal 92 (FIG. 16). In FIG. 16, the lock arm 96 is pushed by a base plate 98 of the terminal 92 to be deflected inward. In this deflected state, a fore end of the second bar 95 abuts against a side surface of the lock arm 96 when the spacer 97 (FIG. 15) is inserted. This prevents a further advance of the spacer 97, recognizing the incomplete insertion of the terminal 92. In this incomplete insertion state, the first bar 94 also has not locked the rear step 93 of the terminal 92.
However, in the conventional structure for recognizing the terminal incomplete insertion, sane workers try to forcibly push further the spacer 97 to fully advance it even when the bar 95 of the spacer 97 is abutting against the lock arm 96 of the connector housing 91. Sometimes, this forcible operation has caused the lock arm 96 to deflect in a significantly curved shape in its lateral (width) direction. This has arisen a permanent deformation or damage of the lock arm 96.
In view of the above-described disadvantage, an object of the invention is to provide an electrical connector having an improved structure for recognizing an incomplete insertion state of a terminal in a connector housing. A resilient lock arm disposed in the connector housing deflects in the incomplete insertion of the terminal so that a spacer abuts against a side surface of the lock arm to restrict a further advance of the spacer for recognizing the terminal incomplete insertion. The improved structure prevents a permanent deformation and damage of the lock arm even when the spacer is forcibly pushed against the lock arm in the abutting state of the spacer against the lock arm.
For achieving the object, an electrical connector of a first aspect of the invention includes a connector housing, a resilient lock arm disposed in the connector housing for locking a terminal, a spacer sliding in the connector housing for additionally locking the terminal inserted in the connector housing, and a projection formed on the resilient arm. The spacer abuts against a side surface of the lock arm when the resilient lock arm is deflecting in an incomplete insertion state of the terminal in the connector housing for recognizing the incomplete insertion of the terminal. The projection abuts against the terminal in an advance direction of the spacer in the incomplete insertion state of the terminal. The projection may be a flat bar extending in a longitudinal direction of the lock arm. Furthermore, the projection may be sandwiched between a pair of elastic pieces fitted on the terminal.
An electrical connector of a second aspect of the invention includes a connector housing, a resilient lock arm disposed in the connector housing for locking a terminal, a spacer inserted in the connector housing for additionally locking the terminal inserted in the connector housing, a projection formed on the lock arm, and an engagement portion provided in the connector housing. The spacer abuts against the lock arm when the lock arm is deflecting in an incomplete insertion state of the terminal in the connector housing for recognizing the incomplete insertion of the terminal. The projection advances into the engagement portion by the deflection of the lock arm in the incomplete insertion state of the terminal. The projection may be formed on a fore end of the lock arm. The projection may have a shape of a rectangular flat bar. The connector housing may be formed with a guide surface continuous with the engagement portion.
An electrical connector of a third aspect of the invention includes a connector housing, a resilient lock arm disposed in the connector housing for locking a terminal received in the connector housing, and a spacer inserted in the connector housing for additionally locking the terminal inserted in the connector housing. The spacer abuts against one of a pair of side surfaces of the lock arm which is deflected in an incomplete insertion state of the terminal in the connector housing for recognizing the incomplete insertion of the terminal. The connector housing has a wall closely adjacent to the other side wall of the lock arm when the lock arm is deflecting, The wall of the connector housing being positioned in an opposite side of the lock arm to the spacer in the incomplete insertion state of the terminal. The wall of the connector housing may be an embossed wall positioned to have a clearance from the lock arm, and the clearance is smaller than an elastic deflection limit of the lock arm.
Now, operational effects of the present invention will be discussed. As described above, in the first aspect of the invention, when the terminal is incompletely inserted, the lock arm deflected by the terminal abuts against the leading end of the spacer at the side surface of the lock arm. This prevents a further advance of the spacer, recognizing the incomplete insertion of the spacer. At the same time, the projection of the lock arm abuts against the terminal in the spacer insertion direction, preventing the lock arm from deflecting laterally (perpendicular to the normal deflection direction). Thereby, this eliminates a permanent deformation, damage, etc. of the lock arm. The lock arm prevented from deflecting the spacer advancing direction allows a more reliable recognition of the terminal incomplete insertion. The elongated projection has an increased area to abut against the terminal, decentralizing the pushing force exerted by the spacer. This eliminates a permanent deformation, damage, etc. of the terminal and the elongated projection. The lock arm prevented from deflecting laterally allows a more reliable recognition of the terminal incomplete insertion.
The first aspect of the invention applies an existing shape for the resilient electrical contact piece to abut against the projection of the lock arm. No new abutting portion of the terminal against the projection is required, which is advantageous in time and cost. The resilient contact piece receives resiliently the force acted on the spacer, preventing a permanent deformation, damage, etc. of the projection and the spacer.
In the second aspect of the invention, when the terminal is incompletely inserted, the locking arm deflected by the terminal engages the projection of the lock arm with the engage portion of the connector housing. Thereby, the lock arm is retained stably at each end thereof, that is, at the root portion and at the protrusion. Thus, even when the spacer abuts against a side surface of the lock arm, the lock arm does not deflect laterally, preventing a permanent deformation, damage, etc. of the lock arm. The deformation limitation of the lock arm in the spacer insertion direction allows a more reliable recognition of the incomplete insertion of the terminal. In the complete insertion state of the terminal, the resiliency of the lock arm causes the protrusion advanced in the engagement portion to disengage from the engagement hole, and the lock arm locks surely the terminal. In addition, the present invention prevents the lateral deflection of the terminal regardless of the shape of the terminal. Furthermore, in an additional aspect of the invention, the lock arm is retained at each end, that is, at the free fore end and at the root portion of the lock arm. This increases significantly the lateral rigidity of the lock arm against a lateral bending force, preventing a lateral deformation of the lock arm to allow a more reliable recognition of the incomplete insertion of the terminal. Moreover, since the plate protrusion deflects in its thickness direction, the protrusion can engage with and disengage from the engagement portion with ease, preventing a permanent deformation, damage, etc. of the protrusion. In addition, the protrusion advances into the engagement portion along the inclined guide surface and disengage from the engagement portion along the inclined guide surface. This allows smooth, reliable engagement and disengagement thereof.
In the third aspect of the invention, when the terminal is incompletely inserted, the lock arm deflected by the terminal abuts against the leading end of the spacer at the side surface of the lock arm. This causes the other side surface of the lock arm to abut against the embossed wall of the connector housing, so that the lock arm does not deflect laterally, preventing a permanent deformation, damage, etc. of the lock arm. The limited deformation of the lock arm in the spacer insertion direction allows a more reliable recognition of the incomplete insertion of the terminal. Particularly, the direct abutment of the side surface of the lock arm against the embossed wall prevents surely the lateral deformation of the lock arm. In addition, the embossed wall is used also as an inner wall for retaining the terminal, reducing the accommodation chamber in manufacturing cost. Moreover, regardless of the shape of the terminal, the lateral deflection of the lock arm is prevented.